[PATCH] spi: fsi: Increase timeout and ensure status is checked

[PATCH] spi: fsi: Increase timeout and ensure status is checked

[Eddie James]

Only timeout after at least one iteration of checking the
status registers. In addition, increase the transfer timeout
to 1 second.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
---
 drivers/spi/spi-fsi.c | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/drivers/spi/spi-fsi.c b/drivers/spi/spi-fsi.c
index 72ab066ce552..cf1e4f9ebd72 100644
--- a/drivers/spi/spi-fsi.c
+++ b/drivers/spi/spi-fsi.c
@@ -24,8 +24,7 @@
 #define FSI2SPI_IRQ			0x20
 
 #define SPI_FSI_BASE			0x70000
-#define SPI_FSI_INIT_TIMEOUT_MS		1000
-#define SPI_FSI_STATUS_TIMEOUT_MS	100
+#define SPI_FSI_TIMEOUT_MS		1000
 #define SPI_FSI_MAX_RX_SIZE		8
 #define SPI_FSI_MAX_TX_SIZE		40
 
@@ -299,6 +298,7 @@ static void fsi_spi_sequence_init(struct fsi_spi_sequence *seq)
 static int fsi_spi_transfer_data(struct fsi_spi *ctx,
 				 struct spi_transfer *transfer)
 {
+	int loops;
 	int rc = 0;
 	unsigned long end;
 	u64 status = 0ULL;
@@ -317,9 +317,10 @@ static int fsi_spi_transfer_data(struct fsi_spi *ctx,
 			if (rc)
 				return rc;
 
-			end = jiffies + msecs_to_jiffies(SPI_FSI_STATUS_TIMEOUT_MS);
+			loops = 0;
+			end = jiffies + msecs_to_jiffies(SPI_FSI_TIMEOUT_MS);
 			do {
-				if (time_after(jiffies, end))
+				if (loops++ && time_after(jiffies, end))
 					return -ETIMEDOUT;
 
 				rc = fsi_spi_status(ctx, &status, "TX");
@@ -335,9 +336,10 @@ static int fsi_spi_transfer_data(struct fsi_spi *ctx,
 		u8 *rx = transfer->rx_buf;
 
 		while (transfer->len > recv) {
-			end = jiffies + msecs_to_jiffies(SPI_FSI_STATUS_TIMEOUT_MS);
+			loops = 0;
+			end = jiffies + msecs_to_jiffies(SPI_FSI_TIMEOUT_MS);
 			do {
-				if (time_after(jiffies, end))
+				if (loops++ && time_after(jiffies, end))
 					return -ETIMEDOUT;
 
 				rc = fsi_spi_status(ctx, &status, "RX");
@@ -359,6 +361,7 @@ static int fsi_spi_transfer_data(struct fsi_spi *ctx,
 
 static int fsi_spi_transfer_init(struct fsi_spi *ctx)
 {
+	int loops = 0;
 	int rc;
 	bool reset = false;
 	unsigned long end;
@@ -369,9 +372,9 @@ static int fsi_spi_transfer_init(struct fsi_spi *ctx)
 		SPI_FSI_CLOCK_CFG_SCK_NO_DEL |
 		FIELD_PREP(SPI_FSI_CLOCK_CFG_SCK_DIV, 19);
 
-	end = jiffies + msecs_to_jiffies(SPI_FSI_INIT_TIMEOUT_MS);
+	end = jiffies + msecs_to_jiffies(SPI_FSI_TIMEOUT_MS);
 	do {
-		if (time_after(jiffies, end))
+		if (loops++ && time_after(jiffies, end))
 			return -ETIMEDOUT;
 
 		rc = fsi_spi_read_reg(ctx, SPI_FSI_STATUS, &status);
-- 
2.31.1

Re: [PATCH] spi: fsi: Increase timeout and ensure status is checked

[Mark Brown]

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On Thu, Jun 23, 2022 at 09:05:47AM -0500, Eddie James wrote:
> Only timeout after at least one iteration of checking the
> status registers. In addition, increase the transfer timeout
> to 1 second.

For bonus fun points the timeout could be based off the expected time
taken for the transfer to complete.

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Re: [PATCH] spi: fsi: Increase timeout and ensure status is checked

[Mark Brown]

On Thu, 23 Jun 2022 09:05:47 -0500, Eddie James wrote:
> Only timeout after at least one iteration of checking the
> status registers. In addition, increase the transfer timeout
> to 1 second.
> 
> 

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git for-next

Thanks!

[1/1] spi: fsi: Increase timeout and ensure status is checked
      commit: 40308f9642a85c30fa7cc5ab8672020cb96ecb66

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark